Finding the Fourth Proportional to 7,784.51, 10,665.88 and 7,680.62

Step by Step Solution

1. Step 1: Write the proportion equation
   7,784.51 : 10,665.88 = 7,680.62 : x
2. Step 2: Convert to fraction form
   7,784.51/10,665.88 = 7,680.62/x
3. Step 3: Cross multiply
   7,784.51x = 10,665.88 × 7,680.62
4. Step 4: Simplify right side
   7,784.51x = 81,920,578.71
5. Step 5: Solve for x
   x = 81,920,578.71/7,784.51
6. Step 6: Final answer
   x = 10,523.54